1. Technical Field of the Invention
The present invention relates in general to the field of communications systems, and in particular, by way of example but not limitation, to scheduling packets of data/informational flows having differing priority levels in a communications system.
2. Description of Related Art
Access to and use of wireless networks is becoming increasingly important and popular for business, social, and recreational purposes. Users of wireless networks now rely on them for both voice and data communications. Furthermore, an ever increasing number of users demand both an increasing array of services and capabilities as well as greater bandwidth for activities such as Internet surfing. To address and meet the demands for new services and greater bandwidth, the wireless communications industry constantly strives to improve the number of services and the throughput of their wireless networks. Expanding and improving the infrastructure necessary to provide additional services and higher bandwidth is an expensive and manpower-intensive undertaking. Moreover, high-bandwidth data streams will eventually be demanded by consumers to support features such as real-time audio-visual downloads and live audio-visual communication between two or more people. In the future, it will therefore become necessary and/or more cost-effective to introduce next generation wireless system(s) instead of attempting to upgrade existing system(s).
To that end, the wireless communications industry intends to continue to improve the capabilities of the technology upon which it relies and that it makes available to its customers by deploying next generation system(s). Protocols for a next-generation standard that is designed to meet the developing needs of wireless customers is being standardized by the 3rd Generation Partnership Project (3GPP). The set of protocols is known collectively as the Universal Mobile Telecommunications System (UMTS).
Referring now to FIG. 1, an exemplary wireless communications system with which the present invention may be advantageously employed is illustrated generally at.100. In a UMTS network 100, the network 100 includes a core network 120 and a UMTS Terrestrial Radio Access Network (UTRAN) 130. The UTRAN 130 is composed of, at least partially, a number of Radio Network Controllers (RNCs) 140, each of which may be coupled to one or more neighboring Node Bs 150. Each Node B 150 is responsible for a given geographical cell. and the controlling RNC 140 is responsible for routing user and signaling data between that Node B 150 and the core network 120. All of the RNCs 140 may be directly or indirectly coupled to one another. A general outline of the UTRAN 130 is given in Technical Specification TS 25.401 V2.0.0 (1999-09) of the 3rd Generation Partnership Project, 3GPP, which is hereby incorporated by reference in its entirety herein. The UMTS network.100 also includes multiple user equipments (UEs) 110. UE may include, for example, mobile stations, mobile terminals, laptops/personal digital assistants (PDAs) with wireless links, etc.
In conventional wireless systems, data transmissions and/or access requests compete for bandwidth based on first come, first served and/or random paradigms. Each mobile station, and its associated transmissions, typically acquire access to a network using some type of request (e.g., a message) prior to establishing a connection. Once the mobile station has established a connection, the mobile station receives a predetermined transmission bandwidth that is usually mandated by the air interface requirements of the relevant system. In a UMTS network, on the other hand, transmission bandwidth is variable, more flexible, and somewhat separated from the physical channel maximum mandated by-the air interface requirements of UMTS. However, certain guaranteed bandwidth and/or quality of service (Qos) requirements must be provided to the UEs. There is therefore a need to ensure that the guaranteed bandwidth and/or QoS is provided to each respective UE in the variable and flexible environment of UMTS.